SFS Models

Features of SFS Models

These couplings have disc springs that use steel for the body. They are the basic type of SERVO FLEX. Single-element types with high torsional stiffness, flexible double-element types that separate double elements with a spacer, and floating shaft types that combine double elements with intermediate flanges are available.

Wide line-up

Both SFS S single-element types with high torsional stiffness, flexible SFS W double-element types that separate double elements with a spacer, and SFS G types that support even longer distances between shafts are available.

Electroless nickel plating also available

Products finished with electroless nickel plating as the surface treatment may be selected for pilot bore couplings and key/set screw couplings.

High-precision mounting

The SFS S/W/G-[ ] M- [ ] M types use friction couplings. They are designed to have the sleeve inserted inside the flange, so they can be mounted very precisely, using the outer diameter of the sleeve as a guide.

Can be assembled from part components

Since we deliver products as components, you can safely use them even in designs that cannot be mounted once assembled. Products can also be shipped pre-assembled, upon request. And since the flanges have interchangeable mounting dimensions, you can order products that have a pilot-bore coupling on the flange of only one side, combined with key/set screw type flanges and high-precision friction coupled flanges.

*The moment of inertia and mass are measured for the maximum bore diameter.

[Dimensions]

SFS-□S

Unit ［mm］

Model

d1, d2

D

N

L

LF

S

F

K

M

Pilot bore

Min.

Max.

SFS-05S

7

8

20

56

32

45

20

5

11

24

4-M5×22

SFS-06S

7

8

25

68

40

56

25

6

10

30

4-M6×25

SFS-08S

10

11

35

82

54

66

30

6

11

38

4-M6×29

SFS-09S

10

11

38

94

58

68

30

8

21

42

4-M8×36

SFS-10S

15

16

42

104

68

80

35

10

16

48

4-M8×36

SFS-12S

18

19

50

126

78

91

40

11

23

54

4-M10×45

SFS-14S

20

22

60

144

88

102

45

12

31

61

4-M12×54

*Pilot bores are to be drilled into the part. See the standard hole-drilling standards for information on bore drilling.

*The nominal diameter of the reamer bolt is equal to the quantity minus the nominal diameter of the screw threads times the nominal length.

[Dimensions]

SFS-□S-□M-□M

Unit ［mm］

Model

Bore diameter

d1

d2

D

N1

N2

L

LF1

LF2

S

C

K

M

M1

M2

SFS-06S

□M-□M

12, 14, 15

12, 14, 15

68

40

40

65.6

25

25

6

4.8

30

4-M6×25

4-M5

2-M5

SFS-08S

□M-□M

15, 16, 20, 22

15, 16, 20, 22

82

54

54

75.6

30

30

6

4.8

38

4-M6×29

4-M6

2-M6

SFS-09S

□M-□M

25, 28

25, 28

94

58

58

77.6

30

30

8

4.8

42

4-M8×36

6-M6

2-M6

□M-35M

25, 28

35

68

85.6

38

SFS-10S

□M-□M

25, 28, 30, 35

25, 28, 30, 35

104

68

68

89.6

35

35

10

4.8

48

4-M8×36

6-M6

2-M6

SFS-12S

□M-□M*1

30, 35

30, 35

126

78

78

101.6

40

40

11

5.3

54

4-M10×45

4-M8

2-M8

SFS-14S

35M-35M

35

35

144

88

88

112.6

45

45

12

5.3

61

4-M12×54

6-M8

2-M8

*The nominal diameters of each bolt and tap are equal to the quantity minus the nominal diameter of the screw threads times the nominal length. The quantities for the pressure bolt M1 and detachment screw hole M2 are quantities for the hub on one side.

*The rated torque of SFS-12S-30M- □ M in note *1 is limited by the ø30 shaft coupling mechanism and is 380 N·m.

*The recommended processing tolerance for paired mounting shafts is h7(h6･g6) class. However, for a shaft diameter of ø35, the tolerance is －0.025 to ＋0.010.

*The moment of inertia and mass are measured for the maximum bore diameter.

[Dimensions]

SFS-□W

Unit ［mm］

Model

d1, d2

D

N

L

LF

LP

S

F

d3

K

M

Pilot bore

Min.

Max.

SFS-05W

7

8

20

56

32

58

20

8

5

4

20

24

8-M5×15

SFS-06W

7

8

25

68

40

74

25

12

6

3

24

30

8-M6×18

SFS-08W

10

11

35

82

54

84

30

12

6

2

28

38

8-M6×20

SFS-09W

10

11

38

94

58

98

30

22

8

12

32

42

8-M8×27

SFS-10W

15

16

42

104

68

110

35

20

10

7

34

48

8-M8×27

SFS-12W

18

19

50

126

78

127

40

25

11

10

40

54

8-M10×32

SFS-14W

20

22

60

144

88

144

45

30

12

15

46

61

8-M12×38

*Pilot bores are to be drilled into the part. See the standard hole-drilling standards for information on bore drilling.

*The nominal diameter of the reamer bolt is equal to the quantity minus the nominal diameter of the screw threads times the nominal length.

[Dimensions]

SFS-□W-□M-□M

Unit ［mm］

Model

Bore diameter

d1

d2

D

N1

N2

L

LF1

LF2

LP

S

C

d3

K

M

M1

M2

SFS-06W

□M-□M

12, 14, 15

12, 14, 15

68

40

40

83.6

25

25

12

6

4.8

24

30

8-M6×18

4-M5

2-M5

SFS-08W

□M-□M

15, 16, 20, 22

15, 16, 20, 22

82

54

54

93.6

30

30

12

6

4.8

28

38

8-M6×20

4-M6

2-M6

SFS-09W

□M-□M

25, 28

25, 28

94

58

58

107.6

30

30

22

8

4.8

32

42

8-M8×27

6-M6

2-M6

□M-35M

25, 28

35

68

115.6

38

SFS-10W

□M-□M

25, 28, 30, 35

25, 28, 30, 35

104

68

68

119.6

35

35

20

10

4.8

34

48

8-M8×27

6-M6

2-M6

SFS-12W

□M-□M*1

30, 35

30, 35

126

78

78

137.6

40

40

25

11

5.3

40

54

8-M10×32

4-M8

2-M8

SFS-14W

35M-35M

35

35

144

88

88

154.6

45

45

30

12

5.3

46

61

8-M12×38

6-M8

2-M8

*The nominal diameters of each bolt and tap are equal to the quantity minus the nominal diameter of the screw threads times the nominal length. The quantities for the pressure bolt M1 and detachment screw hole M2 are quantities for the hub on one side.

*The rated torque of SFS-12W-30M- □ M in note *1 is limited by the ø35 shaft coupling mechanism and is 380 N·m.

*The recommended processing tolerance for paired mounting shafts is h7(h6･g6) class. However, for a shaft diameter of ø35, the tolerance is －0.025 to ＋0.010.

*The moment of inertia and mass are measured for the maximum bore diameter.

[Dimensions]

SFS-□W

Unit ［mm］

Model

d1, d2

D

N

L

LF

LP

S

F

d3

K

M

Pilot bore

Min.

Max.

SFS-05W

7

8

20

56

32

58

20

8

5

4

20

24

8-M5×15

SFS-06W

7

8

25

68

40

74

25

12

6

3

24

30

8-M6×18

SFS-08W

10

11

35

82

54

84

30

12

6

2

28

38

8-M6×20

SFS-09W

10

11

38

94

58

98

30

22

8

12

32

42

8-M8×27

SFS-10W

15

16

42

104

68

110

35

20

10

7

34

48

8-M8×27

SFS-12W

18

19

50

126

78

127

40

25

11

10

40

54

8-M10×32

SFS-14W

20

22

60

144

88

144

45

30

12

15

46

61

8-M12×38

*Pilot bores are to be drilled into the part. See the standard hole-drilling standards for information on bore drilling.

*The nominal diameter of the reamer bolt is equal to the quantity minus the nominal diameter of the screw threads times the nominal length.

[Dimensions]

SFS-□W-□M-□M

Unit ［mm］

Model

Bore diameter

d1

d2

D

N1

N2

L

LF1

LF2

LP

S

C

d3

K

M

M1

M2

SFS-06W

□M-□M

12, 14, 15

12, 14, 15

68

40

40

83.6

25

25

12

6

4.8

24

30

8-M6×18

4-M5

2-M5

SFS-08W

□M-□M

15, 16, 20, 22

15, 16, 20, 22

82

54

54

93.6

30

30

12

6

4.8

28

38

8-M6×20

4-M6

2-M6

SFS-09W

□M-□M

25, 28

25, 28

94

58

58

107.6

30

30

22

8

4.8

32

42

8-M8×27

6-M6

2-M6

□M-35M

25, 28

35

68

115.6

38

SFS-10W

□M-□M

25, 28, 30, 35

25, 28, 30, 35

104

68

68

119.6

35

35

20

10

4.8

34

48

8-M8×27

6-M6

2-M6

SFS-12W

□M-□M*1

30, 35

30, 35

126

78

78

137.6

40

40

25

11

5.3

40

54

8-M10×32

4-M8

2-M8

SFS-14W

35M-35M

35

35

144

88

88

154.6

45

45

30

12

5.3

46

61

8-M12×38

6-M8

2-M8

*The nominal diameters of each bolt and tap are equal to the quantity minus the nominal diameter of the screw threads times the nominal length. The quantities for the pressure bolt M1 and detachment screw hole M2 are quantities for the hub on one side.

*The rated torque of SFS-12W-30M- □ M in note *1 is limited by the ø35 shaft coupling mechanism and is 380 N·m.

*The recommended processing tolerance for paired mounting shafts is h7(h6･g6) class. However, for a shaft diameter of ø35, the tolerance is －0.025 to ＋0.010.

*The moment of inertia and mass are measured for the maximum bore diameter.

[Dimensions]

SFS-□G

Unit ［mm］

Model

d1, d2

D

N

L

LF

LS

S

F

K

M

Pilot bore

Min.

Max.

SFS-05G

7

8

20

56

32

74

20

24

5

11

24

8-M5×22

SFS-06G

7

8

25

68

40

86

25

24

6

10

30

8-M6×25

SFS-08G

10

11

35

82

54

98

30

26

6

11

38

8-M6×29

SFS-09G

10

11

38

94

58

106

30

30

8

21

42

8-M8×36

SFS-10G

15

16

42

104

68

120

35

30

10

16

48

8-M8×36

SFS-12G

18

19

50

126

78

140

40

38

11

23

54

8-M10×45

SFS-14G

20

22

60

144

88

160

45

46

12

31

61

8-M12×54

*Pilot bores are to be drilled into the part. See the standard hole-drilling standards for information on bore drilling.

*If you require a product with an LS dimension other than that above, contact Miki Pulley with your required dimension. Please contact Miki Pulley for assistance if LS ≧ 1000.

*Please note that when the LS dimension exceeds 100 mm with the electroless nickel plating option (SFS- □ G-C), the insertion length of the shaft cannot exceed the LS dimension.

*The nominal diameter of the reamer bolt M is equal to the quantity minus the nominal diameter of the screw threads times the nominal length.

[Dimensions]

SFS-□G-□M-□M

Unit ［mm］

Model

Bore diameter

d1

d2

D

N1

N2

L

LF1

LF2

LS

S

C

K

M

M1

M2

SFS-06G

□M-□M

12, 14, 15

12, 14, 15

68

40

40

95.6

25

25

24

6

4.8

30

8-M6×25

4-M5

2-M5

SFS-08G

□M-□M

15, 16, 20, 22

15, 16, 20, 22

82

54

54

107.6

30

30

26

6

4.8

38

8-M6×29

4-M6

2-M6

SFS-09G

□M-□M

25, 28

25, 28

94

58

58

115.6

30

30

30

8

4.8

42

8-M8×36

6-M6

2-M6

□M-35M

25, 28

35

68

123.6

38

SFS-10G

□M-□M

25, 28, 30, 35

25, 28, 30, 35

104

68

68

129.6

35

35

30

10

4.8

48

8-M8×36

6-M6

2-M6

SFS-12G

□M-□M*1

30, 35

30, 35

126

78

78

150.6

40

40

38

11

5.3

54

8-M10×45

4-M8

2-M8

SFS-14G

35M-35M

35

35

144

88

88

170.6

45

45

46

12

5.3

61

8-M12×54

6-M8

2-M8

*If you require a product with an LS dimension other than that above, contact Miki Pulley with your required dimension. Please contact Miki Pulley for assistance if LS ≧ 1000.

*The nominal diameters of each bolt and tap are equal to the quantity minus the nominal diameter of the screw threads times the nominal length. The quantities for the pressure bolt M1 and detachment screw hole M2 are quantities for the hub on one side.

*The rated torque of SFS-12G-30M- □ M in note *1 is limited by the ø30 shaft coupling mechanism and is 380 N·m.

*The recommended processing tolerance for paired mounting shafts is h7(h6･g6) class. However, for a shaft diameter of ø35, the tolerance is -0.025 to ＋0.010.

*Bore diameters marked with ● and numbers are supported as standard bore diameter.

*Bore diameters whose fields contain numbers are restricted in their rated torque by the holding power of the shaft connection component because the bore diameter is small. The numbers indicate the rated torque value [N·m].

*Consult Miki Pulley regarding special arrangements for other bore diameters.However, restrictions may apply to the allowable torque in the case of small hole diameters, so please check.

SFS G Types

[Specifications]

Model

Rated torque ［N・m］

Misalignment

Max. rotation speed ［min-1］

Torsional stiffness ［N・m/rad］

Axial stiffness［N/mm］

Moment of inertia ［kg・m2］

Mass ［kg］

Parallel ［mm］

Angular ［°］

Axial ［mm］

SFS-05G

20

0.5

1 (On one side)

±1.2

20000

8000

21

0.20×10-3

0.50

SFS-06G

40

0.5

1 (On one side)

±1.6

16000

14000

22

0.55×10-3

0.90

SFS-08G

80

0.5

1 (On one side)

±2.0

13000

41000

30

1.50×10-3

1.70

SFS-09G

180

0.6

1 (On one side)

±2.4

12000

85000

61

2.90×10-3

2.40

SFS-10G

250

0.6

1 (On one side)

±2.8

10000

125000

80

4.60×10-3

3.30

SFS-12G

450

0.8

1 (On one side)

±3.2

8000

215000

98

11.80×10-3

5.80

SFS-14G

800

0.9

1 (On one side)

±3.6

7000

390000

156

21.20×10-3

8.60

SFS-05G-C

15

0.5

1 (On one side)

±1.2

20000

8000

21

0.20×10-3

0.50

SFS-06G-C

30

0.5

1 (On one side)

±1.6

16000

14000

22

0.55×10-3

0.90

SFS-08G-C

60

0.5

1 (On one side)

±2.0

13000

41000

30

1.50×10-3

1.70

SFS-09G-C

135

0.6

1 (On one side)

±2.4

12000

85000

61

2.90×10-3

2.40

SFS-10G-C

190

0.6

1 (On one side)

±2.8

10000

125000

80

4.60×10-3

3.30

SFS-12G-C

340

0.8

1 (On one side)

±3.2

8000

215000

98

11.80×10-3

5.80

SFS-14G-C

600

0.9

1 (On one side)

±3.6

7000

390000

156

21.20×10-3

8.60

SFS-06G-□M-□M

40

0.5

1 (On one side)

±1.6

5000

14000

22

0.55×10-3

1.10

SFS-08G-□M-□M

80

0.5

1 (On one side)

±2.0

5000

41000

30

1.56×10-3

2.00

SFS-09G-□M-□M

180

0.6

1 (On one side)

±2.4

5000

85000

61

3.10×10-3

2.80

SFS-10G-□M-□M

250

0.6

1 (On one side)

±2.8

5000

125000

80

4.70×10-3

3.50

SFS-12G-□M-□M

450

0.8

1 (On one side)

±3.2

5000

215000

98

12.10×10-3

6.50

SFS-14G-35M-35M

580

0.9

1 (On one side)

±3.6

5000

390000

156

25.31×10-3

10.10

SFS-06G-□M-11C

40

0.5

1 (On one side)

±1.6

5000

14000

22

0.54×10-3

1.00

SFS-06G-15M-16C

40

0.5

1 (On one side)

±1.6

5000

14000

22

0.59×10-3

1.10

SFS-08G-□M-16C

80

0.5

1 (On one side)

±2.0

5000

41000

30

1.47×10-3

1.90

SFS-09G-□M-16C

180

0.6

1 (On one side)

±2.4

5000

85000

61

2.80×10-3

2.60

*Max. rotation speed does not take into account dynamic balance.

*The moment of inertia and mass are measured for the maximum bore diameter.

[Dimensions]

SFS-□G

Unit ［mm］

Model

d1, d2

D

N

L

LF

LS

S

F

K

M

Pilot bore

Min.

Max.

SFS-05G

7

8

20

56

32

74

20

24

5

11

24

8-M5×22

SFS-06G

7

8

25

68

40

86

25

24

6

10

30

8-M6×25

SFS-08G

10

11

35

82

54

98

30

26

6

11

38

8-M6×29

SFS-09G

10

11

38

94

58

106

30

30

8

21

42

8-M8×36

SFS-10G

15

16

42

104

68

120

35

30

10

16

48

8-M8×36

SFS-12G

18

19

50

126

78

140

40

38

11

23

54

8-M10×45

SFS-14G

20

22

60

144

88

160

45

46

12

31

61

8-M12×54

*Pilot bores are to be drilled into the part. See the standard hole-drilling standards for information on bore drilling.

*If you require a product with an LS dimension other than that above, contact Miki Pulley with your required dimension. Please contact Miki Pulley for assistance if LS ≧ 1000.

*Please note that when the LS dimension exceeds 100 mm with the electroless nickel plating option (SFS- □ G-C), the insertion length of the shaft cannot exceed the LS dimension.

*The nominal diameter of the reamer bolt M is equal to the quantity minus the nominal diameter of the screw threads times the nominal length.

[Dimensions]

SFS-□G-□M-□M

Unit ［mm］

Model

Bore diameter

d1

d2

D

N1

N2

L

LF1

LF2

LS

S

C

K

M

M1

M2

SFS-06G

□M-□M

12, 14, 15

12, 14, 15

68

40

40

95.6

25

25

24

6

4.8

30

8-M6×25

4-M5

2-M5

SFS-08G

□M-□M

15, 16, 20, 22

15, 16, 20, 22

82

54

54

107.6

30

30

26

6

4.8

38

8-M6×29

4-M6

2-M6

SFS-09G

□M-□M

25, 28

25, 28

94

58

58

115.6

30

30

30

8

4.8

42

8-M8×36

6-M6

2-M6

□M-35M

25, 28

35

68

123.6

38

SFS-10G

□M-□M

25, 28, 30, 35

25, 28, 30, 35

104

68

68

129.6

35

35

30

10

4.8

48

8-M8×36

6-M6

2-M6

SFS-12G

□M-□M*1

30, 35

30, 35

126

78

78

150.6

40

40

38

11

5.3

54

8-M10×45

4-M8

2-M8

SFS-14G

35M-35M

35

35

144

88

88

170.6

45

45

46

12

5.3

61

8-M12×54

6-M8

2-M8

*If you require a product with an LS dimension other than that above, contact Miki Pulley with your required dimension. Please contact Miki Pulley for assistance if LS ≧ 1000.

*The nominal diameters of each bolt and tap are equal to the quantity minus the nominal diameter of the screw threads times the nominal length. The quantities for the pressure bolt M1 and detachment screw hole M2 are quantities for the hub on one side.

*The rated torque of SFS-12G-30M- □ M in note *1 is limited by the ø30 shaft coupling mechanism and is 380 N·m.

*The recommended processing tolerance for paired mounting shafts is h7(h6･g6) class. However, for a shaft diameter of ø35, the tolerance is -0.025 to ＋0.010.

*Bore diameters marked with ● and numbers are supported as standard bore diameter.

*Bore diameters whose fields contain numbers are restricted in their rated torque by the holding power of the shaft connection component because the bore diameter is small. The numbers indicate the rated torque value [N·m].

*Consult Miki Pulley regarding special arrangements for other bore diameters.However, restrictions may apply to the allowable torque in the case of small hole diameters, so please check.